More aggressively inline optimized code.

BUG=
R=danno@chromium.org, mstarzinger@chromium.org, titzer@chromium.org

Review URL: https://codereview.chromium.org/19504006

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@15703 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Calls to HCheckFunction can be eliminated if the value is an HConstant.

Reland "Calls to HCheckFunction can be eliminated if the value is an HConstant"
(https://codereview.chromium.org/18751003/).

The CL failed because of heap snapshot issues. alph@chromium.org just checked in
a fix for that (https://code.google.com/p/v8/source/detail?r=15694).

BUG=
R=danno@chromium.org

Review URL: https://codereview.chromium.org/19504007

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@15704 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Do not call reinterpret_cast when converting from NULL.

If NULL is a nullptr (such as on my FreeBSD system), it is not possible to
use reinterpret_cast to convert it to another pointer. Plus, just using NULL
directly achieves the same effect.

R=ulan@chromium.org

Review URL: https://chromiumcodereview.appspot.com/19388005

Patch from Raphael Kubo da Costa <raphael.kubo.da.costa@intel.com>.

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@15705 ce2b1a6d-e550-0410-aec6-3dcde31c8c00